Nectar notifier/toolbar

After doing a clean up in firefox, I can no longer see the nectar toolbar add-on (used in UK to gain points when clicking n websites). When trying to reinstall, it i not showing up on the firefox add-od list. Can anyone help please?

Exactly the same question here - Has anyone got any answers?

Try contacting the developer for updates. It’s possible that they took down the extension from our site, or that it’s pending publication due to review issues.

I have repeatedly tried to add Nectar toolbar to Firefox on my new PC but Firefox apparently wont allow this. I use my Nectar card all the time when shopping so this is a nuisance.
How can I over-ride Mozilla with my preference?